You will need to get the one from the Chrome store. Make sure you get the Chrome Extension add-on from the Opera store @https://addons.opera.com/en/extensions/details/install-chrome-extensions/
Afterwards, when you install it from the Chrome Extension store @https://chrome.google.com/webstore/detail/finance-toolbar-real-time/cichbngoomgnobmmjpagmbkimbamigie?hl=en
You will need to sign up for a free account @https://iexcloud.io and Verify the Email sent
then you will need to go to "API Tokens" and don't copy the "Secret API" copy the "Publishable API Token" and then you will need to Right-Click your Finance Toolbar extension at the top, go to Options > Advanced Options, and paste the API Token there.
It's explained with images here: https://www.stefanvd.net/support/browser-extension/answer/how-to-add-the-finance-toolbar-api-code
Just Scroll down enough to see it.